Abstract
We present a calculation of the shifts and lifetimes of hydrogen-atom excited states in the vicinity of a jellium surface. The calculations combine accurate density-functional potentials with a complex scaling theory for obtaining resonances by means of bound-state procedures. The lifetimes of the hydrogen levels are found to be 1 to 3 orders of magnitude longer than previous estimates, a fact that has important experimental consequences. Extensions of the approach developed here should have applications to a variety of phenomena involving quasibond states in condensed-phase systems.